Cylinder barrel with protective coating



March 24, 1959 R. F. GoETzE CYLINDER BARREL WITH PROTECTIVE COMING Filed June 15, 1955 United States Patent O CYLINDER BARREL WITH PROTECTIVE COATING Rolf Friedrich Goetze, Burscheid, near Koln, Germany,

assignor to Goetzewerke Friedrich Goetze Aktiengesellschaft, Burscheid, near Koln, Germany Application June 15, 1955, Serial No. 515,674 Claims priority, application Germany July 30, 1954 7 Claims. (Cl. 309-3) The present invention relates to a cylinder barrel more particularly for combustion engines, in which the barrel is surrounded by a cooling agent. As a rule, water is used for cooling cylinder barrels.

The outer surface of the cylinder barrel which is in contact with the coolant is frequently subject to corrosion. Attempts have already been made to protect cylinder barrels against corrosion, by plating them with chromium, or tin, or by coating them with varnish. However, this was only partly successful since the prevailing suction enhances corrosion and will destroy even the hardest chromium coatings.

According to the present invention, a protective coating for the outer surface of the cylinder barrel, which is in contact with the coolant, is made of a resilient soft material. Best suited for the purpose is natural or synthetic soft rubber which is preferably firmly united with the supporting surface, for instance by glueing, vulcanizing, or spraying. Such coatings, contrary to expectation, are very resistant to electrolytic or other chemical attacks of the coolant, even though the latter be mixed with chemical additives and in rapid circulation.

The coating may cover the entire surface of the barrel which is in contact with the coolant. In some cases, however, it may be desirable to coat the barrel only in places which are particularly exposed yto corrosion, more particularly the part of the barrel facing the inlet through which the current of coolant enters and impinges upon the barrel.

The invention will now be more fully described with reference to the accompanying drawing but it should be understood that this is given by way of illustration and not of limitation and that many changes can be made in the details without departing from the spirit of the invention.

In the drawing, which illustrates a cylinder barrel with the coating according to the invention in longitudinal section, the cylinder block of a combustion engine is designated by 1, the barrel by 2. Between the barrel and the block there remains a free space for the coolant; into this space, water is supplied from the outside. A coating 3, made of soft rubber, is applied to the outside of the barrel so as to be in contact with the coolant.

The arrangement according to the invention is particularly suitable for so-called we cylinder barrels. It should, however, be understood that the invention can likewise be applied to other walls of cooling chambers which are subject to corrosion, for instance walls of refrigerators, and the like. These may be protected by a resilient coating of soft material in a manner similar to the one above described.

52,879,116 Patented Mar. 24, 1959 ICC 2. In combination with a cylinder barrel exposed to high temperatures and surrounded by a circulating liquid cooling agent impinging upon the outer surface of said barrel, a corrosionand cavitation-resistant coating on the outer surface of the barrel, said coating consisting of a resilient soft material, whereby the outer surface of the cylinder barrel is made impervious to chemical destruction by the coolant.

3. In combination with a cylinder barrel of an internal combustion engine exposed to high temperatures and surrounded by a circulating liquid cooling agent impinging upon the outer surface of said barrel, a corrosion-resistant coating on the outer surface of the barrel, said coating consisting of a resilient soft material, whereby the outer surface of the cylinder barrel is made impervious to chemical destruction by the coolant.

4. In combination with a cylinder barrel exposed to high temperatures and surrounded by a circulating liquid cooling agent impinging upon the outer surface of said barrel, a corrosion-resistant coating on the outer surface of the barrel, said coating consisting of soft rubber, whereby the outer surface of the cylinder barrel is made impervious to chemical destruction by the coolant.

5. In combination with a cylinder barrel exposed to high temperatures and surrounded by a circulating liquid cooling agent impinging upon the outer surface of said barrel, a corrosion-resistant coating on the outer surface of the barrel, said coating consisting of a resilient soft material rmly secured to said outer surface of the barrel, whereby the outer surface of the cylinder barrel is made impervious to chemical destruction by the coolant.

6. In combination with a cylinder barrel exposed to high temperatures and surrounded by a circulating liquid cooling agent impinging upon the outer surface of said barrel, a corrosion-resistant coating on the outer surface of the barrel, said coating consisting of a resilient soft material provided at the areas of greatest exposure of the barrel to corrosion, whereby the outer surface of the cylinder barrel is made impervious to chemical destruction by the coolant.

7. In combination with a cylinder barrel exposed to high temperatures and surrounded by a circulating liquid cooling agent impinging upon the outer surface of said barrel, a corrosion-resistant coating on the outer surface of the barrel, said coating consisting of a resilient soft material at the portion facing the inlet, whereby the outer surface of the cylinder barrel is made impervious to chemical destruction by the coolant.

References Cited in the le of this patent UNITED STATES PATENTS 679,367 Darling July 30, 1901 2,246,392 Spreng et al. June 17, 1941 2,279,671 Ford April 14, 1942 2,304,589 Nickerson Dec. 8, 1942D 

